But in some cases, anecdotal evidence can be used to help drive scientific research forward. One 17-year-old UK teenager named Deryn Blackwell was given a new lease on life, and his mother attributes his survival to cannabis.

At age 10, Deryn was diagnosed with a rare and ultra-aggressive form of leukemia. After he failed to recover following multiple rounds of chemotherapy and radiotherapy, doctors told his parents, Simon and Callie Blackwell, that there was little more they could do to save their son.

After a doctor denied the Blackwell family’s request for a cannabis-based painkiller, Deryn’s parents turned to the black market in desperation. After buying marijuana from a drug dealer, Simon and Callie turned it into oil at home using a pressure cooker and an online instructional.

While Callie Blackwell originally sought out cannabis to relieve her son’s anxiety and pain while he was in hospice, the teenager eventually made a miraculous recovery. His mother has attributed his survival to marijuana, but some cancer experts have taken the results with a grain of salt.

“Because it’s just one person’s story, without a doctor analysing all the clinical evidence and comparing him to somebody that didn’t get cannabis, we still don’t know for certain it was the cannabis that helped him,” said Dr. Emma Smith, the science information manager for Cancer Research UK.

Unfortunately, without the ability to conduct controlled studies on the effect that cannabis has on fighting cancer, it’s difficult for researchers to pinpoint its precise impact. But many scientists believe that Deryn’s case proves the need for extensive research, and it seems that the UK is finally starting to get the ball rolling.

Earlier this month, Oxford University announced that it will spend up to $12 million to research the benefits of medical cannabis, particularly in regard to cancer, pain, and inflammatory diseases. Additionally, a clinical trial conducted on the only licensed cannabis-based medicine allowed in

Britain, a mouth spray called Sativex, showed that the drug helped treat a certain form of brain cancer.

It’s difficult to prove that the plant was the main factor in Deryn’s amazing recovery from leukemia, but it’s hard to believe that it didn’t at least play a partial role. Either way, the fact remains that we will not fully understand how cannabis might benefit cancer patients until further research is allowed. When you couple anecdotal cases like this one from the Blackwell family with impending studies by pioneering institutions such as Oxford, it seems that it might not be long until this potential treatment is given the shot that it deserves.